Some clippy fixes #918

Job	Run time
Test aarch64-apple-tvos	2m 48s
Test CUDA support	51s
Rustfmt	8s
MSRV (ubuntu-latest)	29s
Test (stable)	26s
MSRV (windows-latest)	42s
Test (beta)	24s
Test (nightly)	37s
Test (linux32)	41s
Test (macos)	47s
Test (aarch64-ios)	45s
Test (win32)	59s
Test (win64)	1m 1s
Test (mingw32)	1m 35s
Test (mingw64)	1m 2s
Test (windows-2019)	1m 23s
Test (windows-aarch64, windows-latest, stable, aarch64-pc-windows-msvc, --no-run)	1m 48s
	16m 26s

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